A common type of bifocal lens consists of
Show answer & explanation
Correct answer: C
Explanation
Correct Answer:
A concave and a convex lens
Explanation:
A common bifocal lens is typically prescribed for individuals suffering from presbyopia (an age-related condition where a person has difficulty focusing on both distant and nearby objects). In a standard bifocal, the upper portion consists of a concave lens used for viewing distant objects clearly, while the lower portion features a convex lens (reading segment) used for reading or close-up work.
Additional Points:
Presbyopia occurs naturally with aging as the eye's crystalline lens loses flexibility and the ciliary muscles weaken.
Important Questions/Answers:
Question: Which type of lens is used to correct presbyopia?
Answer: Bifocal lens.
Question: Which lens type is positioned in the upper half of a standard bifocal glasses lens?
Answer: Concave lens (for distance vision).